Electric switch



May 18, 1954 o. RICHARDSON 2,678,975

ELECTRIC SWITCH Filed Feb. 19; 1953 3 Sheets-Sheet 1 ne, z A

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May 18, 1954 o. RICHARDSON 2,678,975

\ ELECTRIC swrrcH Filed Feb. 19, 1953 5 Sheetsshe9t 2 0., n, n @im my?? n, .m 0W w m WW/W// w 0^ 2, M Irl* m# H s 4 .fl M l E ,d s 3 1 M M 5 j i.. Y N 5 wm im@ m 63 A m 6 m f@ R E o. a s f5 3 fo .w 4s M m ff///// If w w .4 m .m 9 ww m 9 m. w mw rr 2 w. M 2 F M n Patented May 18, 1954 UNITED STATES 'EENT GFFICE poration of Georgia Appncaticn February 19, 1953, serial No. 337,781

(o1. 20w-4s) 16 Claims. i This invention relates to electric switches 'and more particularly to operating mechanisms for high voltage switches of the air break or disconnect type.

In switches of the type wherein a switch blade is movable about a pivotal mounting relative to a iixed contact and wherein the blade is rotatable about its longitudinal axis to establish :high pressure contact with the spaced jaws of the cooperating fixed contact, an operating mechanism is required which is capable of applying the proper forces to the switch throughout the switch opening and closing strokes. Since the cooperating parts of the switch operating mechanism must change their relative Vpositions during an operating stroke and since the paths of travel of the various elements of the switch and its operating mechanism do not inherently produce the desired switch movement, it has been the practice to utilize mechanisms which are provided with lost motion connections or which incorporate yieldable elements or which produce some undesired switch movements in order Vto avoid a tendency of the parts to become jammed when in certain positions. For example, a switch which utilizes yieldable elements or lost motion connections is disclosed in Patent 2,520,036 Guss'ow and Curtis granted August 22, 1950, 'and assigned to the assignee ci this invention.

A principal object of this invention is to provide an improved operating mechanism by which positive and smooth operating movement may be obtained in switches of the type in which a movable blade is rotatable about its longitudinal axis and movable about a pivotal mounting in order to open and close vthe controlled circuit.

Another object of this invention is the .provision of a switch operating mechanism by which a uniform switch movement is obtained which is entirely independent of the effects of gravity or other external forces.

A further object of this invention is to provide a switch operating mechanism which "is readily adjustable so as precisely to predetermine the relative positions of the movable and fixed contacts of the switch and so as to render theswitch easily and smoothly operable.

A still further object of this invention is the provision of an improved switch operating mech- 'anism which is relatively free of `friction and which is constructed with ample leverage to faiord easy and positive operation of the switch under all service conditions likely to be encountered.

The `invention in one form as applied to a high voltage electric switch having a blade which is rotatableabout its longitudinal axis and which is pivotally mounted for swinging movement utilizes cam means interconnected with a vuniversal joint to establish a driving relationship between the switch blade-and a driving crank movable in a plane which is disposed transverse to the plane of swinging movement of the switch blade.

For a better understanding of the invention reference may be had to the following description taken in conjunction with the accompanying drawings in which Fig. l is a plan view of a switch embodying the invention; Fig. 2 is a side elevation ofthe switch shown in Fig. l; Fig. 3 is a partial end view ofthe switch shown in Fig. 1 with the blade represented as being in the closed position; Fig. 4 is a view similar to Fig. 3 with the switch parts shown just prior to the nal contact engaging movement or just subsequent to the initial contact disengaging movement; Fig. 5 is a partial side view of the switch operating mechanism showing the parts in the fully opened position; Fig. 6 is a partial section View on the line 6 6 of Fig. 2 showing the parts when the switch is fully closed; Fig. 7 is a cross-section view of the driving and driven members of the switch operating mechanism which are constructed according to the invention; Fig. 8 is a plan View partially in section along the line 8-8 of Fig. 2; Fig. 9 is a side view partially in section of the structure represented in Fig. 8 together with certain parts associated therewith; Fig. 10 is a view similar to Fig. '7 and represents a modification of the invention; Fig. l1 is a view similar to Figs. 7 and l0 and represents another modification of the invention; Figs. 12 and 13 are side and end views respectively of structure similar to that shown in Figs. 7, 10 and l1 and which represents still another modification of the invention; Fig. 14 represents a still further modincation o'f the invention; and Fig. l5 is a schematic view of a mechanism such as is shown in Fig. 14 but with a different relationship to the universal joint.

As is indicated in Figs. l and 2, the switch parts are mounted on a base member l which may be in the form of a metallic channel member. Afxed to the left-hand end of the base element i is an insulator stack 2 and a similar insulator stackV 3 is securely ixed in position on the righthand end of the base member i. A switch terminal 4 is aiixed to the top of the fixed insulator stack 2 `and is 'in electrical contact with the fixed jaw contact comprising jaw elements 5 and 6. The other terminal of the switch is indicated by the numeral I and as is clearly shown in Figs. 1 and 2 is formed integrally with a yoke element S which is secured by bolts 9 atop the xed insulator 3. As is shown in Figs. 1 and 2 the lefthand end of the yoke element 8 is provided with a pair of prongs I and II which terminate in a downwardly extending portion I2 which is interconnected with a rotatable insulator I3 by a journal connection schematically represented at Iii in Fig. 2. Rotatable insulator I3 is provided with a journal mounting at the lower extremity of the metallic element I5 as schematically represented at I6. Secured to the metallic extension I5 is an operating crank Ia to which force is applied to rotate the insulator stack I3. In View of the above description it will be obvious that the yoke element 8, having its right-hand end securely affixed by the bolts 9 to the iixed insulator 3, serves as a bearing for the upper end of the insulator stack I3 and as such lends support thereto. The yoke element 8 also serves as a mounting means for the jaw contacts 'l and I8 which are secured to the yoke element S by means of the bolts I9. In addition to acting as a bearing support for the insulator stack I3 and as support means for the jaw contacts I7 and i3 the yoke element 8 also serves to support the pivot 20 for the hinge element 2I of the switch blade generally designated by the numeral 22. As is represented in Figs. 1 and 2 the switch blade 22 comprises a tubular element 23 to the left-hand end of which is affixed a contact tip 24 and to an intermediate portion thereof is aixed a contact tip 25. Aflixed to the right-hand end of the blade 23 is a tubular extension 26 which is rotatable within the hinge element 2i and which is provided at its right-hand extremity with an element 2l which is provided with a pivot 28. Thus with the parts in the position shown in Figs. 1, 2, and 3 the contact tips 24 and 25 are in engagement with the jaw contacts 5 and 6 and il and I3 respectively and the circuit is complete through the switch from terminal 4, contacts 5 and 6, contact tip 24, tubular element 23, contact tip 25, jaw contacts I7 and IB, yoke element 8, and terminal '1.

High pressure contact is achieved in known manner by the blade tips 24 and 25 when disposed horizontally so as to stress the jaw contacts E and 6 and Il and I8 as represented in Fig. 3. When it is desired to open the switch, the blade portion 23 and parts associated therewith are rotated about the longitudinal axis of the switch blade to a position wherein the contact tips 2li and 25 do not engage the jaw contacts 5 and 3 and il and I3 as represented in Fig. 4. Thereafter the circuit opening operation is completed by causing the switch blade to swing about the hinged pivot 23 to the position represented in Fig. 5. This complex motion of the switch blade 22 is imparted thereto by means of the crank 29 which is rotated by means of the crank I3 acting through rotatable insulator I3 and which is interrelated with the blade 22 through a linkage and cam mechanism constructed according to this invention. As already explained, the crank 23 is rotatable with the insulator stack I3, this crank 23 being anixed thereto at the collar I3. As is shown in Fig. 9, the downwardly extending portion I2 of the yoke member 3 is provided with a neck portion 30 to which is affixed a washer 3l by means of a nut 32, these parts forming a bearing connection through the opening 32 formed in the crank element 23. y

According to this invention the crank 29 is provided with a suitable driving member which may constitute the rounded end portion 33 of the crank or which may be in the form of a sleeve 33a as indicated in Fig. 7. Disposed within the end portion 33 is a driven element 34 which is provided at its upper end with a follower pin 35 and with a transversely extended follower pin 33 at its lower end. From Figs. 6 and '7 it will be understood that the upper end of the driving sleeve 33a is provided with a pair of diametrically disposed recesses 37 and that the lower end of this sleeve is provided with a pair of diametrically disposed projections 33, these recesses 31 and projections 38 being cooperable with the pins 35 and 36 respectively. The driving element 34 is interconnected with a link member 39 by a universal joint comprising the pins i0 and 35 and the element 4I. Link 33 is interconnected with the extension 2l of the blade 22 by means of the pivot 2G. As is best shown in Fig. 6 the end portion 33 of crank 23 is provided with a pair of recesses 42 which coincide with recesses 3l in sleeve 33a and projections t3 are arranged on the lower portion of element 33 to coincide with projections 33 on sleeve 33a.

Figs. 6 and 8 respectively represent the link 39 and the crank 29 in a solid line position designated by the leter A and in addition represent these parts in a dotted line position represented by the letter B. Position A corresponds to the fully closed position of the blade 22. Position B corresponds to the position of the parts during a switch operating movement after the switch blade has been rotated about its longitudinal axis but before any appreciable swinging movement of the blade about the pivot 23 has occurred during an opening operation. It will be understood that the crank 23 and its driving element 33-33a move in an arcuate path in a horizontal plane. It will furthermore be understood that the lower extremity of the link 39 and parts associated therewith swing in a down-and-up arcuate path during the cone-like movement of link 39. Thus it will be understood that as the link 39 swings from the position designated by the letter A to that designated by the letter B the pin 40 will move downwardly to a position midway between positions A and B and thereafter will move upwardly to the position B so as to describe an arcuate path which when viewed in plan as represented in Fig. 8' is arcuate due to the arc described by the driving element 33 of the crank 29 when moved about its center position. Since the driven member 34 and the link 39 and parts associated therewith do not rotate about their own axes during travel between positions A and B and since the driving element 3.3--33a does change its angular position relative to the center of rotation of the crank 29, there is necessarily a relative rotary movement between the driving element 33-33a and the driven element 34. Since the driving element 33 during its movement in an arcuate path does not move in the vertical direction and since the link 39 and parts associated therewith must move vertically, I provide suitable cam means for accommodating this divergence in the vertical movement of these two parts while maintaining a positive relationship therebetween. Thus in accordance with a feature of this invention the recesses 37 in the driving element 33a and recesses (i2 in crank 33 receive the pin 35 during the time when the parts are moving from position A to position B. Similarly the lower pin 36 is caused to ride over the projections 3B in the sleeve 33a and the projections servante" formed oirl the lower surta-'ceptv thel driving element' 33". Thus theen'd's* of elements-^33` and' 33'a and pins v35L and 35*L constitute cam' means.

AfterV the partsV move through theJ mid-position I between positions A andI B' the pin 35 begins to rideoutof the cam surfaces* 31' and Hand-con# tinues `about .theupper end surfaces of the driving" element 33e-33a and' by the" same" token the pin 33 rides'over them projecting portions 38' and 43" and continues to move about thelo'wer` end portion of thedriving element' 33--33a;

A'sis" understood" in' the art, continued movement of the operatngjcrank" 29from the position designated by the. letter' B tothep'osition' designated' by' the letter' C. causes the switchblade 22 to Swiig about the' pivot 20 from the position indicatedin Figs; 1i and 2' to` that representedby Fig`.15'.

The arrangement'disclosedin Fig. l0 represents" amodification of that disclosed in Figs; 5, 6, and' 'Il The arrangement ofFig. 1'0 constitutes what-Ii presently consider to be a preferred ernbodiment of the invention.

In Fig. 1`0 the driven element 34 is provided with a wide groove 44 for minimizing` frictional effects between that element and the sleeve 33a and in addition bearingsleeves 45 are provided to reduce the frictional losses between these parts. Bearings 45 could be of metallic material impregnated witha lubricating substance. For further reducing fiictional eiects, the pins 35 and 39'. may be respectively provided with rollers 45 andl 4T which, if desired, could be mounted on roller bearings. As is indicated in Fig. l the portion 33 ofthe crank 29v is formed of a split constructionwith projecting tabs 48 and a bolt 49 arranged to form a. gripping relationship about the driving sleeve 33o. If desired, the driving element 33a may be secured in position within the element 33 by means of a tapered pin 59 so as to maintain the parts securely in position. One possible advantage of the arrangement shown in Fig. 10 Yis that the driven element 3ft and the driving element 33 and parts associated therewith may be constructed as a subassembly and furthermore these parts are readily adjustable relative to the driving element 33 before the pin Ellis inserted in position. As in Figs. 3, 6, and Z the upper and lower ends of sleeve 33a are respectively provided with surfaces 31a and 38a. Un n like Figs. 6 and '7, Fig. 10 does not require cam surfaces in element 33 since sleeve 33a is long enough to prevent rollers 49 and..41 from engaging the ends of member 33.

The modification shown in Fig. 11 utilizes a driving element 33 in the form of an opening in crank 29 and the driven element 34 is provided withV atransverse pin I on the ends of which roller elements 52 are mounted. A collar ele ment 53 is disposedV about the upper end of the driven element 34 and may be held in position by the gripping action of the upper end of the element 33 due to the tightening'of the nut54 which cooperates with the bolt 55 andthe projecting tabs 53. Similarly a collar 53a is disposed about4 thetlower'portion of the element 34 and issecured within the driving. element 33 by means ofv the nut 54a, the bolt 55a and the projecting tabs 56a. If desired, tlie collars" 53`and 53a. may be secured in. position by means of the tapered pins 50 and 53a.. The collar 53 is provided with diametrically opposite projections 37b and lthe collar 53af is' provided with diametricall'y vopposite recessed. portions 38o.. Thus' swinging movement of the crank arm 29 causes the rollers-alteridaalon'ga path deflnedlbycanrsurfacesl31'15andiwli;v

In the arrangement-shown in- Figs. 1-2fandf-.13 the driven element 3ft` isprovidedi withl a groove; the irregular upper surface off which is indicated at 3io and the irregular lower surface of which is indicatedat 38C and projecting pins which are' laterally adjustable andwhicn are designated? by l the numeral 51 are-arrangedwiththe inner ends`A thereof disposed within'the groove or groovesin the element 34. If desired, ball bearings 58C may' be providedl Relativemotionin a vertical direc-- tion between the parts 33' and 34v isk accom@- modated by the irregular portion 31o-38o ofthev groove formed in the driven element 34;

In Fig. 14v the' crank 23 isl provided with` anopeningin which the-drivingA element 59-is affixed by clamping action offtabs 60, bolt 6l and nut- 62. Pin 63Vcan be used-if desired to maintain the'V element 59 securely in position: Disposed within the driving element 59"i"sa transverse pin E4'- providedV with rollers 65T. AnV inverted' cup-shaped driven member 53 is provided with diametrica-lly opposite recesses 31d. A short sleeve 5T havingv an internal fiange Bf is secured by threads 69- and set screw 'E0 to the element 66. Projections 38d are formed in the flange 68` to correspond-to the recesses-31d` in element 66. Thismodicati'on has the advantage of affording protection against precipitation.

The arrangement shown in Fig. 15 is like that of Fig. 14 except that in Fig. l5 the universal joint is interposed between the drivingl crank 29' and the cam means comprising V'elements 64'; 65;' 55, and 6T. Also the crank 39 forms a'V unitary connecting link between theV cam means and thel pin 29. The universal joint comprises the small' end portion 13 of crank 29, the pin'il and the element 72. Element 65 is formed integrallywith crank 39.

From the above description it will be understood that according tothe-invention, I' have provided an improved switch operating mechanism wherein positive control of the switch is maintained by the mechanismY at all times. Furthermorefit will` be understood that I achieve this result with a mechanism which does not have a tendency to jam orto` ride through so-c'allcd hard spots. It will also be `appreciated that' gravity or other externalV forcesv cannot cause movement of thev switch blade relative to the operating mechanism.

While I have shown and described several embodiments of the invention, IA do not wish to be limited thereto and intend in the appended claims to cover 'all such changes and modications as all within the true spirit and scope of the invenion.

What I claim as new and desireto secure by Letters Patent of the United States is':

l. An electric switch comprising a fixed contact,` a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to'said iixed contact, a crank niovablein a plane transversely disposed relative to the plane of swinging movement of said blade, a" link having one end thereof pivotally con# nected with said blade, and means including cam means interconnected between said crank 'and the yother end of said link for establishing a positive operative relationship therebetween.

2. An electric switch comprising a xed contact, a switch blade rotatable about its longitudinal axis land pivotally mounted. for swinging movement relative to said fixed' contact, a crank' n'l'ovablefi-n-a planetransversely'disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, and means including cam means interconnected between said crank 'and the other end of said link for establishing a positive operative relationship therebetween, said cam means including a driven member operably related with said link and a driving member operably related with said crank, one of said members having a cam surface engaging a corresponding surface of the other of said members so as to impart controlled operating movement to said switch blade in response to operating movement of said crank.

3. An electric switch comprising a iixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said fixed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, and means including cam means interconnected between sad crank and the other end of said link for establishing a positive operative relationship therebetween, said cam means including a driving member operably related with said crank and a cooperating driven member operably related with said link, said members being relatively movable in a direction transverse to the plane in which said crank is movable during a portion of an operating stroke.

4. An electric switch comprising a xed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging lmovement relative to said fixed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, and means including cam means interconnected between said crank and the other end of said link for establishing a positive operative relationship therebetween, said cam means including a driving member operably related with said crank and a telescopically related driven member operably related with said link, said members being coaxially disposed at all rtimes and having engaging surfaces arranged to impart relative movement thereto in an axial direction during at least a portion of the rotary movement of said blade in response to rotary displacement of said driving member relative to said driven member.

5. An electric switch comprising a xed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said fixed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, and means including cam means interconnected between said crank and the other end of said link for establishing a positive operative relationship therebetween, said cam means including a driven member operably related with said link and a driving member operably related with said crank, one of said members having a cam surface engaging a corresponding surface of the other of said members so as to impart controlled operating movement to said switch blade in response to operating movement of said crank and said members being adjustable relative to said crank in a direction transverse to the plane in which said crank is movable.

6. An electric switch comprising a xed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said fixed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, a driven member connected with the other end of said link by a universal joint, and a driving member operably related with said crank, the cooperating surfaces of said members constituting cam means for establishing a positive operating relationship between said driving and said driven members during at least a substantial portion of an operating stroke of said blade and in a direction normal to the plane in which said crank is movable.

7. An electric switch comprising a fixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said xed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a driven member operably related with said blade, and a driving member connected with said crank by a universal joint, said driving and said driven members having cooperating cam surfaces congured to establish a positive operative relationship therebetween.

8. An electric switch comprising a xed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted intermediate its ends for swinging movement relative to said lfixed contact, a crank movable in an arcuate path in a vplane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with one end of said blade, a driven member connected with the other end of said link by a universal joint, and a driving member movable with said crank and telescopically related with said driven member, the engaging surfaces of said members constituting cam means for imparting relative movement to said members in a direction axially thereof in response to operating movement of said crank and rotary motion of said driving member relative to said driven member.

9. An electric switch comprising a iixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted intermediate its ends for swinging movement relative to said fixed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, the swing end of said crank being formed with an opening therein, a link having one end thereof pivotally connected with one end of said blade, a driven member connected with the other end of said link by a universal joint and disposed in said opening in said crank, said driven member and said crank being provided with engaging surfaces configured to impart motion to said driven member in a direction substantially normal to the plane in which said crank moves during at least a portion of the operating movement of said switch, and means for operating said crank.

lO. An arrangement according to claim 9 wherein the opening in said crank extends in a direction generally normal to the plane in which said crank is movable, wherein projecting means extends inwardly from a wall defining said opening, and wherein the driven member comprises an element having an irregular groove formed in its surface for receiving said projecting means so that rotary movement of the swing end of said crank relative to said driven member results in relative movement therebetween in a direction generally normal to the plane in which said crank is movable.

l1. An arrangement according to claim 9 wherein the opening in said crank extends in a direction generally normal to the plane in which said crank is movable, wherein projecting means extends inwardly from a wall defining said opening, wherein the driven member comprises an element having an irregular groove formed in its surface for receiving said projecting means so that rotary movement of the swing end of said crank defining said opening relative to said driven member results in relative movement therebetween in a direction generally normal to the plane in which said crank is movable, and wherein bearing means is disposed within said opening about said element.

12. An electric switch comprising a fixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said fixed Contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, the swing end of said crank being formed with an opening therein, a link having one end thereof pivotally connected with said blade, a cup-shaped element having an irregular path along an inside wall thereof and connected with the other end of said link by a universal `ioint, a pin disposed in the opening in said crank and having a transversely disposed follower element for riding in the path in the wall of said cup-shaped element thereby to accommodate relative movement therebetween in a direction transverse to the plane of movement of said crank in response to movement of said crank.

13, An electric switch comprising a .fixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said xed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, a driven member connected with the other end of said link by a universal joint, and a driving member operably related with said crank, the cooperating surfaces of said members being configured so that movement of said crank results in controlled relative movement of said members during at least a portion of an operating stroke of said blade and in a direction normal to the plane in which said crank is movable, said driving member comprising a sleeve supported by said crank and having irregularly shaped end surfaces and said driven member comprising an element disposed within said sleeve and provided at each end thereof with follower means disposed to cooperate with said end surfaces of said sleeve.

14. An electric switch comprising a fixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said fixed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, a driven member connected with the other end of said link by a universal joint, and a driving member operably related with said crank, the cooperating surfaces of said members being congured so that movement of said crank results in controlled relative movement of said members during at least a portion of an operating stroke of said blade and in a direction normal to the plane in which said crank is movable, said driving member comprising a sleeve movable with said crank and having irregularly shaped end portions and said driven member comp-rising an element disposed within said sleeve and provided at each end with roller means arranged to cooperate with said end portions of said sleeve, and said crank being provided with holding means for adjustably positioning said sleeve and said element.

l5. An electric switch comprising a fixed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted for swinging movement relative to said xed contact, a crank movable in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with said blade, a driven member connected with the other end of said link by a universal joint, a driving member operably related with said crank, the cooperating surfaces of said members being configured so that movement of said crank results in controlled relative movement of said members during at least a portion of an operating stroke of said blade and in a direction normal to the plane in which said crank is movable, said driving member comprising a sleeve movable with and supported by said crank and formed with irregularly shaped end surfaces and said driven member ocmprising an element disposed within said sleeve and provided at each end with roller means disposed to engage and follow said end surfaces of said sleeve in response to relative rotary motion of said sleeve and said element, and bearing means interposed between the inner surface of said sleeve and said element.

16. An electric switch comprising a xed contact, a switch blade rotatable about its longitudinal axis and pivotally mounted intermediate its ends for swinging movement relative to said fixed contact, a crank movable in an arcuate path in a plane transversely disposed relative to the plane of swinging movement of said blade, a link having one end thereof pivotally connected with one end of said blade, a driven member connected with the other end of said link by a universal joint, a driving member movable with said crank and telescopically related with said driven member, the engaging surfaces of said members being configured to impart relative movement to said members in a direction axially thereof in response to operating movement of said crank and rotary motion of said driving member relative to said driven member, said driving member comprising an opening in said crank extending in a direction transverse to the plane in which said crank is movable and having an irregular path disposed along the wall of said opening and said driven member comprising an element disposed in said opening and provided with follower means secured thereto and disposed in said path so that relative rotary motion between said crank and said element results in relative movement therebetween in a direction normal to the plane in which said crank is movable.

Name Y Date Gussow et al. Aug. 22, 1950 Number 

